Method and device for testing phase angle jump of grid-connected equipment

Abstract

The invention discloses a method and a device for testing phase angle jump of grid-connected equipment. The method comprises the following steps of: normally starting grid-connected work by tested grid-connected equipment; the controller adjusts the inverter output voltage of the power grid simulation unit on line according to the power grid voltage collected by the first voltage sensor, so that the inverter output voltage of the power grid simulation unit is approximately synchronous with the power grid voltage; a phase angle jump target value is preset, and when the phase angle difference # imgabs0 #, collected by the second voltage sensor, of the inverter output voltage of the power grid simulation unit and the power grid voltage is equal to the preset phase angle jump target value # imgabs1 #, the controller controls the bypass switch to be closed; according to the method, a power grid simulation unit is configured to provide a test power supply for tested grid-connected equipment, the phase difference between output voltage and power grid voltage is adjusted on line, and a bypass switch is controlled to be closed, so that the phase angle jump test of the tested grid-connected equipment is realized. The failure of the large-angle phase angle jump test caused by excitation surge current impact generated by the tested equipment box transformer substation during the large-range phase angle jump test is avoided, and the efficiency of the phase angle jump test is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of grid-connected equipment testing, and in particular to a method and device for testing phase angle jump of grid-connected equipment. Background Art

[0002] With the promotion and application of new standards such as NB / T 31054-2024 and GB / T 19964-2024, new energy grid-connected equipment needs to undergo phase angle jump adaptability testing.

[0003] The prior art generally performs phase angle jump tests on grid-connected equipment by directly changing the phase angle of the output voltage of a power grid simulation device. When the test point is on the 35kV high-voltage side, the grid-connected equipment under test generally includes a box transformer. When performing a large-angle phase angle jump test, the box transformer of the grid-connected equipment under test is prone to magnetic saturation due to a sudden change in the voltage phase angle, thereby generating an excitation surge current, causing the power grid simulation device to trigger the output overcurrent protection, resulting in the failure of the large-angle phase angle jump test. Summary of the invention

[0004] The technical problem to be solved by the present invention is to propose a phase angle jump test method for grid-connected equipment. The phase angle jump test method for grid-connected equipment provides a test power supply to the grid-connected equipment under test by configuring a power grid simulation unit, adjusts the phase difference between the output voltage and the power grid voltage online, and controls the closing of a bypass switch to realize the phase angle jump test of the grid-connected equipment under test, thereby avoiding the failure of a large-angle phase angle jump test caused by the excitation surge current impact generated by the box transformer of the equipment under test during a large-range phase angle jump test, thereby improving the efficiency of the phase angle jump test.

[0005] In order to solve the above technical problems, the present invention provides a phase angle jump test method for a grid-connected device, which adopts a phase angle jump test device for a grid-connected device. The phase angle jump test device for a grid-connected device comprises a bypass switch K1, a first voltage sensor, a second voltage sensor, an input switch K2, a power grid simulation unit, an output switch and a controller. The input end of the bypass switch K1 is respectively connected to the first voltage sensor, the input end of the input switch K2 and the power grid, the output end of the bypass switch K1 is respectively connected to the second voltage sensor, the output end of the output switch K3 and the tested grid-connected device, the output end of the input switch K2 is connected to the input end of the power grid simulation unit, and the output end of the power grid simulation unit is connected to the input end of the output switch K3; the method comprises the following steps:

[0006] The controller controls the bypass switch K1 to be disconnected and the input switch K2 to be closed, and controls the rectifier of the grid simulation unit to work according to the grid voltage collected by the first voltage sensor; the controller controls the output switch K3 to be closed and controls the inverter of the grid simulation unit to output according to the preset voltage, and the grid-connected equipment under test starts and works normally; the controller adjusts the inverter output voltage of the grid simulation unit online according to the grid voltage collected by the first voltage sensor, so that the inverter output voltage of the grid simulation unit is nearly synchronized with the grid voltage; the phase angle jump target value is preset, and when the phase angle difference between the inverter output voltage of the grid simulation unit collected by the second voltage sensor and the grid voltage is The preset phase angle jump target value When they are equal, the controller controls the bypass switch K1 to close.

[0007] Preferably, the step of "the controller online adjusts the inverter output voltage of the grid simulation unit according to the grid voltage collected by the first voltage sensor, so that the inverter output voltage of the grid simulation unit is close to synchronization with the grid voltage" specifically includes:

[0008] The controller calculates the grid voltage amplitude U according to the grid voltage collected by the first voltage sensor grid and grid voltage frequency f;

[0009] The controller sets the grid voltage amplitude U grid and the grid voltage frequency f as the inverter output voltage amplitude given reference quantity and frequency given reference quantity of the grid simulation unit and generate the inverter output voltage wave quantity of the grid simulation unit;

[0010] The controller controls the operation of the switching device of the inverter according to the output voltage ripple amount of the inverter.

[0011] Preferably, the step of "when the phase angle difference between the inverter output voltage of the grid simulation unit and the grid voltage acquired by the second voltage sensor is equal to a preset phase angle jump target value, the controller controls the bypass switch to close" specifically includes:

[0012] The controller calculates the collected grid voltage phase angle in real time The inverter output voltage phase angle of the power grid simulation unit collected by the second voltage sensor And calculate the phase difference between the output voltage and the grid voltage

[0013] The controller jumps the target value according to the preset phase angle Adjust the phase difference between the output voltage and the grid voltage

[0014] When the output voltage and the grid voltage phase difference Equal to the phase angle jump target value When , the controller controls the bypass switch K1 to close.

[0015] Preferably, the grid-connected device under test is any one of a wind turbine, a photovoltaic power generation unit, and an energy storage system.

[0016] In order to solve the above technical problems, the present invention also discloses a phase angle jump test device for grid-connected equipment, wherein the phase angle jump test device adopts the phase angle jump test method according to claim 1, and the phase angle jump test device for grid-connected equipment comprises a bypass switch K1, a first voltage sensor, a second voltage sensor, an input switch K2, a power grid simulation unit, an output switch K3 and a controller, wherein the input end of the bypass switch K1 is respectively connected to the first voltage sensor, the input end of the input switch K2 and the power grid, the output end of the bypass switch K1 is respectively connected to the second voltage sensor, the output end of the output switch K3 and the grid-connected equipment under test, the output end of the input switch K2 is connected to the input end of the power grid simulation unit, and the output end of the power grid simulation unit is connected to the input end of the output switch K3.

[0017] After adopting the above method and device, the grid-connected equipment phase angle jump test method adopts the grid-connected equipment phase angle jump test device, the grid-connected equipment phase angle jump test device includes a bypass switch K1, a first voltage sensor, a second voltage sensor, an input switch K2, a power grid simulation unit, an output switch and a controller, the input end of the bypass switch K1 is respectively connected to the first voltage sensor, the input end of the input switch K2 and the power grid, the output end of the bypass switch K1 is respectively connected to the second voltage sensor, the output end of the output switch K3 and the tested grid-connected equipment, the output end of the input switch K2 is connected to the input end of the power grid simulation unit, and the output end of the power grid simulation unit is connected to the input end of the output switch K3; the method comprises the following steps:

[0018] The controller controls the bypass switch K1 to be disconnected and the input switch K2 to be closed, and controls the rectifier of the grid simulation unit to work according to the grid voltage collected by the first voltage sensor; the controller controls the output switch K3 to be closed and controls the inverter of the grid simulation unit to output according to the preset voltage, and the grid-connected equipment under test starts and works normally; the controller adjusts the inverter output voltage of the grid simulation unit online according to the grid voltage collected by the first voltage sensor, so that the inverter output voltage of the grid simulation unit is nearly synchronized with the grid voltage; the phase angle jump target value is preset, and when the phase angle difference between the inverter output voltage of the grid simulation unit collected by the second voltage sensor and the grid voltage is The preset phase angle jump target value When the voltages are equal, the controller controls the bypass switch K1 to close. The grid-connected device phase angle jump test method configures the grid simulation unit to provide the test power supply to the grid-connected device under test, adjusts the phase difference between the output voltage and the grid voltage online, and controls the bypass switch to close to realize the phase angle jump test of the grid-connected device under test. This avoids the failure of the large-angle phase angle jump test caused by the excitation surge current impact generated by the box transformer of the tested device during the large-range phase angle jump test, thereby improving the efficiency of the phase angle jump test. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is an overall system diagram of the grid-connected equipment phase angle jump test device of the present invention;

[0020] Figure 2 The present invention is a flowchart of the overall working process of a phase angle jump test device for grid-connected equipment.

[0021] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0022] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer and more understandable, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0023] In the description of the present application, it should be understood that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "front", "back", "left", "right", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0024] Embodiment 1

[0025] See also Figure 1 and Figure 2 , Figure 1 This is an overall system diagram of the grid-connected equipment phase angle jump test device of the present invention, Figure 2 The present invention is a flowchart of the overall working process of a phase angle jump test device for grid-connected equipment.

[0026] The present embodiment discloses a phase angle jump test method for a grid-connected device, which adopts a phase angle jump test device for a grid-connected device. The phase angle jump test device for a grid-connected device comprises a bypass switch K1, a first voltage sensor 21, a second voltage sensor 22, an input switch K2, a power grid simulation unit 50, an output switch K3 and a controller 60. The input end of the bypass switch K1 is respectively connected to the first voltage sensor, the input end of the input switch and the power grid, the output end of the bypass switch is respectively connected to the second voltage sensor, the output end of the output switch and the grid-connected device under test, the output end of the input switch is connected to the input end of the power grid simulation unit, and the output end of the power grid simulation unit is connected to the input end of the output switch. The method comprises the following steps:

[0027] The controller 60 controls the bypass switch K1 to be disconnected and the input switch K2 to be closed, and controls the rectifier of the grid simulation unit 50 to work according to the grid voltage collected by the first voltage sensor 21; the controller 60 controls the output switch K3 to be closed and controls the inverter of the grid simulation unit 50 to output according to the preset voltage, and the tested grid-connected device 40 starts the grid-connected work normally; the controller 60 adjusts the inverter output voltage of the grid simulation unit 50 online according to the grid voltage collected by the first voltage sensor 21, so that the inverter output voltage of the grid simulation unit 50 is nearly synchronized with the grid voltage; the preset phase angle jump target value is set, and when the phase angle difference between the inverter output voltage of the grid simulation unit collected by the second voltage sensor 22 and the grid voltage is The preset phase angle jump target value When they are equal, the controller 60 controls the bypass switch to close.

[0028] Embodiment 2

[0029] This embodiment is based on the first embodiment. In this embodiment, the step of "the controller 60 adjusts the inverter output voltage of the grid simulation unit 50 online according to the grid voltage collected by the first voltage sensor 21, so that the inverter output voltage of the grid simulation unit 50 is close to synchronization with the grid voltage" specifically includes:

[0030] The controller 60 calculates the grid voltage amplitude U according to the grid voltage collected by the first voltage sensor 21. grid and grid voltage frequency f;

[0031] The controller 60 sets the grid voltage amplitude U grid and the grid voltage frequency f as the inverter output voltage amplitude given reference quantity and frequency given reference quantity of the grid simulation unit 50 and generate the inverter output voltage wave quantity of the grid simulation unit 50;

[0032] The controller 60 controls the operation of the switching devices of the inverter according to the output voltage ripple amount of the inverter.

[0033] Embodiment 3

[0034] This embodiment is based on the first embodiment. In this embodiment, the step of "when the phase angle difference between the inverter output voltage of the power grid simulation unit 50 and the power grid voltage acquired by the second voltage sensor 22 is equal to the preset phase angle jump target value, the controller controls the bypass switch to close" specifically includes:

[0035] The controller 60 calculates the collected grid voltage phase angle in real time The inverter output voltage phase angle of the power grid simulation unit collected by the second voltage sensor And calculate the phase difference between the output voltage and the grid voltage

[0036] The controller 60 changes the target value according to the preset phase angle Adjust the phase difference between the output voltage and the grid voltage

[0037] When the output voltage and the grid voltage phase difference Equal to the phase angle jump target value When , the controller 60 controls the bypass switch K1 to close.

[0038] Embodiment 4

[0039] This embodiment is based on the first embodiment. In this embodiment, the tested grid-connected device 40 is any one of a wind turbine, a photovoltaic power generation unit, and an energy storage system.

[0040] Embodiment 5

[0041] The present embodiment discloses a phase angle jump test device for a grid-connected device, the phase angle jump test device adopts the phase angle jump test method as described in the first embodiment, the phase angle jump test device for a grid-connected device comprises a bypass switch K1, a first voltage sensor 21, a second voltage sensor 22, an input switch K2, a power grid simulation unit 50, an output switch K3 and a controller 60, the input end of the bypass switch K1 is respectively connected to the first voltage sensor 21, the input end of the input switch K2 and the power grid 30, the output end of the bypass switch K1 is respectively connected to the second voltage sensor 22, the output end of the output switch K3 and the tested grid-connected device 40, the output end of the input switch K2 is connected to the input end of the power grid simulation unit 50, and the output end of the power grid simulation unit 50 is connected to the input end of the output switch K3.

[0042] The phase angle jump test method for grid-connected equipment provides test power to the grid-connected equipment under test by configuring a grid simulation unit, adjusts the phase difference between the output voltage and the grid voltage online, and controls the closing of a bypass switch to realize the phase angle jump test of the grid-connected equipment under test, thereby avoiding the failure of the large-angle phase angle jump test caused by the excitation surge current impact generated by the box transformer of the tested equipment during the large-range phase angle jump test, thereby improving the efficiency of the phase angle jump test.

[0043] The preferred embodiments of the present application are described above with reference to the accompanying drawings, but the scope of the present application is not limited thereby. Any modification, equivalent substitution and improvement made by a person skilled in the art without departing from the scope and essence of the present application shall be within the scope of the present application.

Claims

1. A method for testing phase angle jump of grid-connected equipment, characterized in that: A phase angle jump test device for grid-connected equipment is used, and the phase angle jump test device for grid-connected equipment includes a bypass switch K1, a first voltage sensor, a second voltage sensor, an input switch K2, a power grid simulation unit, an output switch and a controller. The input end of the bypass switch K1 is respectively connected to the first voltage sensor, the input end of the input switch K2 and the power grid, the output end of the bypass switch K1 is respectively connected to the second voltage sensor, the output end of the output switch K3 and the tested grid-connected equipment, the output end of the input switch K2 is connected to the input end of the power grid simulation unit, and the output end of the power grid simulation unit is connected to the input end of the output switch K3; the method comprises the following steps: The controller controls the bypass switch K1 to be opened and the input switch K2 to be closed, and controls the rectifier of the power grid simulation unit to work according to the power grid voltage collected by the first voltage sensor; The controller controls the output switch K3 to close and controls the inverter of the power grid simulation unit to output according to the preset voltage, and the tested grid-connected equipment starts and works normally; The controller adjusts the inverter output voltage of the grid simulation unit online according to the grid voltage collected by the first voltage sensor, so that the inverter output voltage of the grid simulation unit is close to the grid voltage; the phase angle jump target value is preset, and when the phase angle difference between the inverter output voltage of the grid simulation unit collected by the second voltage sensor and the grid voltage is The preset phase angle jump target value When they are equal, the controller controls the bypass switch K1 to close.

2. The grid-connected equipment phase angle jump test method according to claim 1, characterized in that: The step of "the controller online adjusts the inverter output voltage of the grid simulation unit according to the grid voltage collected by the first voltage sensor, so that the inverter output voltage of the grid simulation unit is close to synchronization with the grid voltage" specifically includes: The controller calculates the grid voltage amplitude U according to the grid voltage collected by the first voltage sensor grid and grid voltage frequency f; The controller sets the grid voltage amplitude U grid and the grid voltage frequency f as a given reference quantity for the inverter output voltage amplitude and frequency of the grid simulation unit and generate a given voltage wave quantity for the inverter output voltage of the grid simulation unit; The controller controls the operation of the switching device of the inverter according to the output voltage ripple amount of the inverter.

3. The grid-connected equipment phase angle jump test method according to claim 1, characterized in that: The step of "when the phase angle difference between the inverter output voltage of the grid simulation unit and the grid voltage collected by the second voltage sensor is equal to the preset phase angle jump target value, the controller controls the bypass switch to close" specifically includes: The controller calculates the collected grid voltage phase angle in real time The inverter output voltage phase angle of the power grid simulation unit collected by the second voltage sensor And calculate the phase difference between the output voltage and the grid voltage The controller jumps the target value according to the preset phase angle Adjust the phase difference between the output voltage and the grid voltage When the output voltage and the grid voltage phase difference Equal to the phase angle jump target value When , the controller controls the bypass switch K1 to close.

4. The grid-connected equipment phase angle jump test method according to claim 1, characterized in that: The grid-connected device under test is any one of a wind turbine, a photovoltaic power generation unit, and an energy storage system.

5. A phase angle jump test device for grid-connected equipment, characterized in that: The phase angle jump test device adopts the phase angle jump test method of the grid-connected equipment as claimed in claim 1, and the phase angle jump test device of the grid-connected equipment includes a bypass switch K1, a first voltage sensor, a second voltage sensor, an input switch K2, a power grid simulation unit, an output switch K3 and a controller. The input end of the bypass switch K1 is respectively connected to the first voltage sensor, the input end of the input switch K2 and the power grid, the output end of the bypass switch K1 is respectively connected to the second voltage sensor, the output end of the output switch K3 and the grid-connected equipment under test, the output end of the input switch K2 is connected to the input end of the power grid simulation unit, and the output end of the power grid simulation unit is connected to the input end of the output switch K3.

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